Data are already routinely collected from radio-collared grey wolves in Yellowstone, and scientists have used this information in their latest study to try to get a better picture of the species’ basic responses to a changing environment.

Information collected and analysed has provided insights into how certain aspects of the grey wolf population have altered with the changing environment, including population size, genetics, body size, and even the timing of key life cycle events, such as the age at which they first have pups. The genetics of coat colour was also studied, as the thick coat of the grey wolf in Yellowstone tends to be black or grey, unlike its relatives in Europe.

As well as helping researchers to predict how grey wolves may respond to future climate change, it is hoped that the discoveries made during this research, published in Science this week, could help scientists to predict which species are at an elevated risk of extinction as a result of climate change, and which are more likely to show resilience in the face of environmental alterations.

Grey wolves in Yellowstone tend to have grey or black coats

A reintroduced species

The wolves were tracked from the air by research scientists from the US Department of the Interior, Utah State University and the University of California, who flew across the park by helicopter in order to dart the large carnivores. Once the animals were tranquilised, the scientists descended to the ground to weigh them and take blood samples. In total, more than a decade’s worth of data was collected from the 280 wolves living in Yellowstone.

Despite now thriving in the area surrounding the park, with a total of approximately 1,700 individuals in Montana, Idaho, Wyoming, Oregon and Washington states, grey wolves were driven to extinction in the area in the 1920s. In the late 19th and early 20th centuries, the federal government supported a wolf extermination effort, encouraging people to shoot, poison or trap wolves as a way of preserving livestock. The species was reintroduced to Yellowstone in the mid-1990s, and the recovery plan has been more successful than expected.

Studies of the grey wolf have helped scientists to develop a model to predict which species will be most at risk of extinction as a result of climate change

Applications for the future

For many years, scientists have been working on how to save species from a changing climate, finding that some may move to higher, cooler areas to find suitable homes, potentially running out of space and dying out, whilst others may successfully adapt to their new surroundings, becoming smaller or bigger to suit the changing conditions.

The computer model developed through this new study allows researchers to consider a number of key variables including growth rate, fertility and life span, and predict how these traits, both behavioural and genetic, will be altered as a result of climate change. Tim Coulson, a professor of life sciences at Imperial College London, and leader of the study, explains, “One of the ways people could take our framework is to ask whether animals that are able to adapt body size, or coat colour, are likely to change sufficiently fast so that the animals can cope with change.”

Professor Coulson explains that, although the study does not go into detail with respect to factors such as climate change-induced diseases or changes in prey numbers, the results of this study are not limited to wolf populations, and have far-reaching applications, “In reality we can apply the methods we developed across a range of animals and behaviours.”